Thread: need help picking a cam

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Wow, I love camshaft decisions. So first I'll tell what I have in my 82 'maro. 355 with comp xtreme hydraulic roller 224 intake and 230 exhaust at .050 lift. Thats 276 and 282 for the advertised I think...if I can remember that. The lift is .502 and .510. I have absolutely NO problems with vacuum even if I nail the brakes repeatedly. Albeit there is less power at low, but it really pulls well from 3000 or so on. The low end idle is quite nice and rumbly but its no pro stock, and I have a manual with 3.08 gears in the back currently and by 2200 rpm the car takes off easily, if I ever even have to idle it up that fast to get going. I think the cam works great on the car that it is in. But for a truck you might want to drop down to a smaller cam to haul that fat load around. That way you can keep the small stepped up converter and still have some rumble with the right pipes and have lots of midrange power which would be perfect for cruising the highway. But, again, read techinspectors article because it is very true. However, with my setup I have no vaccum problems and my cam runs really strong for a long duration, mostly in part to the roller setup and heads. I run 10.2 to 1 compression as well and some lighter JE/SRP forged pistons at .030 over so it spools up really fast as well. For a truck though, its up to you and the automatic and rearend ratio. If the rear is steep and your truck is fairly light, you might get away with that, but then forget the highway with steep gears. Your choice, but my suggestion is a slightly smaller cam and put some good pipes and mufflers on it if you want that rumble. Also, if your block wasnt setup for a roller cam then its gonna cost you for lifters. I went roller so I could have a good lowend with a big cam. All in the ramp rates and area under the lift curve, my friend. Good luck with your truck and combo.

And brickman, you can get 1hp per CI with a little work on that, give it a good manifold, carb and a good low/midrange cam. You will NEED to give it headers for that torque to pull that monster around. You can give it 400 hp and about 450 torque without putting a whole lot of money into the setup. With 10-1 compression and a cam change you should be gettin close. Maybe step up the rockers if you want more lift but then it might idle like trash. If you plan to do even a little cleaning of the heads, I would highly suggest a small pocket porting job, you can keep your stock valves but with a 400 you are really coming against the heads' flow capabilities when you try to make power, so even a small increase there will give you quite a bit.

In both cases.....Bigger is not always better....

Good luck on those combos guys, hope I gave some worthwhile advice